When you are on holiday, you can see how valuable a baby carrier is. Instead of pushing the stroller to the beach, you carry your baby. And you can go anywhere. Steps, small paths, sand. No problem. Take nice walks on the beach and eat something in between, with a baby carrier it's all easy to do (but make sure you have good sun protection, preferably clothing, hat and sunscreen).
Going on holiday is also easier with a baby carrier. Service area, quick toilet visit with the sibling is done in no time. If you travel by train or fly by plane, boarding and changing is much easier than with a stroller. It's much easier to get around at the airport or train station. You can even easily pull a suitcase, you have both hands free.